Customisable 'To' field in BBDM/BBIS emails

With the nickname and customisable addressee and salutation name formats, users are able to make sure that constituents are addressed according to their wishes. However, the ‘To’ field in emails sent through BBDM or BBIS are not customisable, which means that despite the constituent’s nickname, addressee and salutation name formats, the ‘To’ field always contains their full name. The only way to make sure that constituents receive emails addressed to their preferred name is to change the first and/or last name fields. We would like the ability to be able to use nickname + surname in the 'To' field.